Several prominent reports have indeed suggested that reversal of aging damage can occur, e.g., in vivo ectopic expression of three (Oct4, Sox2, Klf4) of the four Yamanaka reprogramming factors [202] was able to promote axon regeneration after previous eye injury [203] and also stem multiple aspects of aging-related disease such as renal failure, cardiomyopathies, and diabetic conditions [201]. The gene discussed is KLF4; the disease is kidney failure.